AB1157 HIGH PREVALENCE OF UNDIAGNOSED PSORIATIC ARTHRITIS AMONG PATIENTS WITH PSORIASIS: ALGERIAN MULTICENTER SCREENING SURVEY USING PURE4 QUESIONNAIRE AND CASPAR CRITERIA.
Authors: A. Djebbari, A. Abi Ayad, S. Bennedjema, H. Merouan, S. Oulebsir, B. Abdelatif, Z. Rayhan, B. Saber, A. Noureddine, K. Ahmed, K. Rafik, B. Abderrachid
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Psoriatic arthritis (PsA) is a polymorphic disease, in term of clinical presentation, severity and evolution. Skin lesion precedes joint damage in 84%, therefore, a multidisciplinary approach associating dermatologist and rheumatologist provide an opportunity for earlier diagnosis, more timely therapy and prevention of disability. <h3>Objectives</h3> To provide Algerian epidemiological data on the Prevalence of undiagnosed PsA among psoriasis patients in dermatology practice. This multicenter screening survey is conduct in order to reduce diagnostic delay and prevent progressive joint involvement and disabilities. <h3>Methods</h3> Between 2019 and 2022, a multicenter cross-sectional trial conducted in four Dermatology Clinics in Algeria (Algiers, Blida, Bechar and Constantine); had recruited patients presenting with plaque psoriasis and no prior rheumatologist-confirmed PsA diagnosis. Patients were screened using the Psoriatic arthritis UnclutteRed screening Evaluation (PURE4) questionnaire and were referred to a rheumatologist for assessment of PsA using classification for psoriatic arthritis criteria CASPAR if they had a PURE 4 score ≥1.Psoriasis characteristics: Body surface area, psoriasis types, area, severity index, and psoriasis disability index tools were used for assessing psoriasis patients. <h3>Results</h3> The study included 212 patients with psoriasis:64% were male and 36% female. Their median age was 48.12 yr ±11.74. Referring to the type of psoriasis, 72% presented with plaque psoriasis, 16% guttata 6% pustular and 24% with psoriasis of more than one type. Nail disease appeared in 24 % and scalp disease in 26%. PURE 4 was applied to all 212 psoriasis patients; among them n = 53 (25% of all tested patients) had a score ≥1. The sequential application of PURE4 and CASPAR criteria found a prevalence of undiagnosed PsA of 20.28% [95% CI: 9, 23.5]. The PPV of PURE 4 in this setting is 49.23% [95% CI: 39, 67]. Of these patients, 44% of patients with PsA had psoriatic nail disease and scalp involvement seen in 37%. With reference to the PsA type, 30% patients presented with polyarthritis,44% with oligoarthritis,39% with enthésites, dactylitis in 23% and 13%with axial arthritis. The subgroup of patients with PsA had significantly higher rates of obesity (42%) compared to non-PsA. Patients with severe psoriasis(P = 0.001), nail and scalp involvement (P = 0.003) with chronic plaque psoriasis (P = 0.001)associated with obesity (P = 0.0001)were identified as independent positive predictors of PsA. <h3>Conclusion</h3> Screening for PsA in Algerian patients with psoriasis revealed a significant number of undiagnosed cases (20.28%) that should be treated early. Severe psoriasis nail and scalp involvement, and obesity are factors predicting the PsA development. <h3>References</h3> [1]Reich K, Krüger K, Mössner R, Augustin M. Epidemiology and clinical pattern of psoriatic arthritis in Germany: a prospective interdisciplinary epidemiological study of 1511 patients with plaque-type psoriasis. Br J Dermatol. 2009 [2]Audureau E. Psoriatic arthritis screening by the dermatologist: development and first validation of the "PURE-4 scale." J Eur Acad Dermatol Venereol. 2018;32(11):1950–3 [3]Ana Urruticoechea-Arana and al. Psoriatic arthritis screening: A systematic literature review and experts' recommendations Plos 2021 [4]Su YJ. Early Diagnosis of psoriatic arthritis among psoriasis patients: clinical experience sharing. Clin Rheumatol. 2020 [5]Villani AP. Prevalence of undiagnosed psoriatic arthritis among psoriasis patients: Systematic review and meta-analysis. J Am Acad Dermatol. 2015 [6]Spelman L, Frequency of undiagnosed psoriatic arthritis among psoriasis patients in Australian dermatology practice. J Eur Acad Dermatol Venereol. 2015 <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.